ABSTRACT
Objective To evaluate the clinical value of MRA on the abnormal vessels in Moyamoya and cerebral revascularization , and to evaluate PWI in the observation of cerebral hemodynamics before and after cerebral revascularization.Methods Twenty-four patients with Moyamoya disease ascertained by DSA received cerebral revascularization on one side.MRA and PWI were performed for all patients before and after the operation , while DSA was performed after operation in nine patients to compare the images of MRA and DSA by three experienced radiologists.Perfusion parameters in terminal branches of middle cerebral artery ( MCA) on the operative side were compared with those on the contralateral sides and the cerebellum , including cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and delay time ( DT) , as well as relative ratio ( values on the operative side/values on the contralateral side , and values on the operative side/values on the cerebellar region ) of perfusion parameters (rCBF, rCBV, rMTT and rDT) were calculated.Comparisons of the data between different groups were performed using paired Student′s t test.Results MRA was similar to DSA in displaying the internal carotid artery , main branches stenosis, Moyamoya vessels, and cerebral revascularization.DSA was better in displaying collateral vessels than MRA, but primary images of MRA provided anatomic and pathologic information of cerebral parenchyma.After the operations , rCBF (1.30 ±0.27) and rCBV (1.26 ±0.21) of MCA perfusion regions on the operative and the contralateral sides were higher than rCBF (0.73 ±0.15) and rCBV (0.98 ±0.12) before the operation significantly (t=-7.19,-6.64,P<0.05).rMTT (1.06 ±0.20) and rDT (1.07 ± 0.18) after the operation were lower than rMTT(1.53 ±0.34)and rDT (1.40 ±0.26) before the operation (t=5.62,5.40,P<0.05) .In MCA perfusion regions on the operative and cerebellar sides , rCBF(1.93 ± 0.34)and rCBV(2.25 ±0.35)were higher than rCBF(0.88 ±0.18)and rCBV(1.16 ±0.22)(t=-3.04,-3.06,P<0.05) before the operation.rMTT (1.13 ±0.29) and rDT (1.29 ±0.12) were lower than rMTT (1.88 ±0.19 ) and rDT ( 3.29 ±0.47 ) before the operation ( t =4.01, 4.72, P <0.05 ).Conclusions MRA is a safe , reliable method to evaluate abnormal vessels and cerebral revascularization after the operation in moyamoya disease.PWI can detect poor cerebral perfusion , and can be used for assessment of the effect of cerebral revascularization.
ABSTRACT
Objective To investigate the effects of tetanic stimulation of peripheral nerve on intracranial direct electrical stimulation motor-evoked potentials (MEP) in patients undergoing cerebral functional area operation. Methods Eight patients undergoing elective brain tumor resection under propofol-fentanyl anesthesia with partial neuromuscular blockade were enrolled in the study. Both conventional MEP (C-MEP) monitoring and posttetanic MEP (P-MEP) monitoring were performed throughout the operation for each patient, and the two groups of data were recorded. For one group, direct electrical stimulation with a train of five pulses was delivered to motor cortex and pyramidal tract, C-MEP was unilaterally recorded from the abductor pollicis brevis, and P-MEP was obtained 1 s after tetanic stimulation (frequency 50 Hz, intensity 50 mA, duration 5 s) to the ipsilateral tibial nerve.For the other group, direct electrical stimulation with a train of five pulses was delivered to motor cortex and pyramidal tract, C-MEP was unilaterally recorded from the tibialis anterior, and P-MEP was obtained 1 s after tetanic stimulation (frequency 50 Hz, intensity 50 mA and duration 5 s) to the contralateral tibial nerve. Randomized crossover method was used for C-MEP and P-MEP recording in each group, with an interval of 120 s. The adverse effects were observed. Results Amplitudes of P-MEP from the abductor pollicis brevis and tibialis anterior were significantly higher than those of C-MEP. Three patients had body movement during intraoperative cortex stimulation, while there was no awareness during operation and other electrical stimulation-related nervous system impairment and complications. Conclusion The application of tetanic stimulation of peripheral nerve before direct electrical stimulation can augnent the amplitudes of MEP from the abductor pollicis brevis and tibialis anterior in patients undergoing cerebral functional area operation.
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Objective To know the risk factors of indoor environment associated with childhood asthmas. Methods Using 1∶1 matched case-control study design,140 cases and 140 age-sex-matched controls from the Affiliated Hospital of Ningxia Medical University were investigated for the indoor environment risk factors,from July 2004 to May 2008. Conditional Logistic regression model was used for data analysis. Results It was revealed in univariate and multivariate conditional Logistic regression analysis that there was significant correlation between using coal for cooking,newly indoor decoration,raising pets and the childhood asthma with odds ratios of 1.67,6.46 and 3.06 respectively(P